Modern technology for managing the flow of fluids, in particular in a motor vehicle, implements numerous sensors enabling instantaneous parameter values such as the temperature of the fluid, its pressure, its viscosity, . . . , to be transmitted to one or more computers.
It is thus necessary to equip at least some of the branches of a hydraulic circuit with such sensors, and thus to incorporate in the circuit supports that are suitable firstly to maintain the continuity of the circuit with regard to the fluid, and secondly to hold the sensitive portion of the sensor within the fluid to be monitored.
Each motor vehicle manufacturer has developed its own system for managing fluid flows, and those systems are generally similar from one vehicle to the other, but they are based on measurement points which, in reality, differ substantially from one vehicle to the other. Thus, with regard to the fuel circuit, for example, it is necessary to monitor the temperature of said fuel in the return pipe for returning excess fuel to the tank, which excess fuel comes from the injectors of the injection pump or even from the filter. In some systems, it suffices to know the temperature of the fuel coming from the injectors, others need to know the temperature of the fuel before its common return to the tank. Those different requirement require different mountings for the sensors that are to be put in place. Component manufacturers thus find it difficult to organize manufacture rationally in order to satisfy fully demand that is very diversified.
The present invention seeks to remedy that difficulty, at least in part, by proposing a hydraulic-fluid circuit element having the function of grouping in one body the various pipes that might need to be fitted with a sensor so as to be able to rationalize the manufacture of the body which is to receive at least one sensor in unique manner.
More precisely, the invention provides a junction member for a hydraulic-fluid circuit which comprises a body provided with internal channels opening to the outside through a plurality of connection means capable of co-operating firstly with external pipes, and secondly with the support of at least one sensor for sensing a physical characteristic of the fluid flowing through one of the internal channels of the body.
An advantage of the junction member resides in the fact that it constitutes a single point of intervention on the fluid circuit, thereby making it easier to clean and maintain, in particular when the circuit has motor-vehicle fuel flowing therethrough.
Since the support for the sensor is in the form of a spigot having an end suitable for connection to an active sensor portion, the internal channels of the body of the junction member of the invention include a chamber having a wall that includes the connection means for connecting the support of the sensor in a position such that the active portion of said sensor is situated in the chamber. In this way, a unique interface is provided for positioning sensors, whatever the junctions that are to be made between the various fluid flows arriving or leaving the junction member of the invention.
The chamber is further defined in the body by a wall provided with at least two orifices each extended beyond the chamber by external connection means. This is the simplest embodiment of the invention, in which the active portion of a sensor is held in a single flow of fluid.
In another embodiment of the junction member of the invention, the body includes a third orifice passing through connection means for connecting to an external pipe, while the internal channels include at least one partitioning element for partitioning the chamber, said partitioning element defining, in said chamber, a bypass channel between two of the three above-mentioned orifices, so as to avoid the active portion of the sensor. The presence of the bypass channel enables the junction member of the invention to be used in several ways, depending on whether it is required to sense a parameter value for a single flow or for a mixture of flows.
Finally, it is advantageous for the connection between the body and the sensor support to be rotary, and for the means for connecting the body to the various external pipes to be situated in a plane containing the connection axis for connecting the support to the body.